Field of the Disclosure
The present application relates to surgical robots and associated guidance systems and, more particularly, to a splint device for forming a fiducial marker and/or a tracking marker for the guidance system of a surgical robot used, for example, in dental surgery.
Description of Related Art
Robotic systems are being increasingly implemented in surgical applications. One such example involves a surgical robot used in dental surgery. Such robots are often associated with a guidance system used to guide the surgical instrument implemented by the surgical robot. The guidance system may also be configured to be involved in the surgical pre-planning process, whether by being involved in gathering and/or analyzing patient data, and planning the surgical procedure, or by relying upon pre-planning data to guide the surgical instrument to conduct the surgical procedure.
In particular surgical procedures, some surgical robotic systems rely upon a fixed reference point associated with the patient's body for guiding the surgical robot. That is, some such surgical robotic systems define a frame of reference with respect to the patient's body so as to account or otherwise compensate for movements or motion of the patient during the procedure, whether during pre-planning or during the actual surgical procedure itself. This reference point must also be repeatable such that multiple engagements/disengagements (i.e., periods between pre-planning and the actual surgical procedure) do not change the frame of reference implemented by the surgical robot or the guidance system associated therewith.
In particular instances, the reference point (or the connection between the guidance system and the patient to define that reference point) implemented by the guidance system for the surgical robot may be accomplished through, for example, an optical modality, a mechanical modality, an acoustic modality, or other suitable and appropriate tracking/guiding modality, or combination thereof. In some modalities, particularly used in dental surgery applications, one mechanical modality for forming the reference point (i.e., a “fiducial marker”) may be accomplished, for example, by attaching/securing a rigid element to the head/teeth of the patient. Such a rigid element, in some instances, may be referred to as and may comprise a splint (see, e.g., prior art in FIGS. 1, 2A, and 2B). Such a splint may generally include, for instance, a retainer portion that grips one or more of the teeth (i.e., by way of an adhesive substance, such as an acrylic material applied between the retainer portion and the teeth), a mounting portion (i.e., mounting arm) that connects the retainer portion to a kinematic mount, and the kinematic mount, itself, which may comprise an attachment point for a tracking portion associated with the guidance system for the surgical robot (i.e., wherein, for instance, reflective markers may be mounted to the attachment point for optical tracking of the fiducial marker, or the attachment point may include a securing site for forming a mechanical connection therewith for mechanical tracking of the fiducial marker, or the attachment point may otherwise be configured to receive an appropriate element associated with any other suitable tracking arrangement for the fiducial marker).
In such instances, it may be preferable for the retainer to be as rigid as possible (i.e., the structure of the retainer itself, as well as the fixation thereof to the teeth of the patient) throughout the surgical procedure. However, it may also be preferable for the retainer to be readily removable when the surgical procedure is complete. In some instances, it may be preferable for the retainer to be reproducibly removed and replaced, for example, between the pre-planning procedure (i.e., a CT scan) which may occur on one day (when the retainer must be in place so the fiducial marker(s) associated therewith are captured in the scan), and the surgical procedure may occur on another day (wherein the surgical procedure requires the retainer to be in place for tracking/guiding the surgical procedure).
Such prior art splint devices as shown, for example, in FIGS. 1, 2A, and 2B, also require a careful balance of the adhesive material (i.e., dental acrylic) to be applied in order to be effective in rigidly mounting the retainer portion to the teeth of the patient. For instance, if too little of the adhesive material is applied in the retainer portion, the splint device may be too easily separated from the teeth, since the amount of the adhesive material may not be sufficient to bond the retainer to the teeth to sufficiently resist the forces applied thereto during the surgical procedure. However, if too much of the adhesive material is applied to the retainer portion, the excess adhesive material may flows into the tooth undercuts (i.e., the portion of the tooth where the tooth narrows toward the gum-line and/or the spaces between teeth), the retainer portion will not be removable at the end of the surgical procedure, without, for instance, drilling into the solidified adhesive material to remove the retainer portion from the tooth/teeth. In such instances, the retainer portion will likely not be re-usable for the particular patient, and if further procedures are required, a new retainer portion, including a new mounting portion for the fiducial marker and/or tracking marker, may also be required.
As such, there exists a need for a splint device for forming a fiducial marker for the guidance system of a surgical robot used, for example, in dental surgery which addresses these and other limitations of prior art devices.